It would help to know the exact model number as the one you gave is only a series number. Then I can look up what battery you have.
Press Control/Alt/S for the information menu in windows Or Go to the Start menu and scroll to H/HP Help and Support/HP Support Assistant. Open the program and click on your computer in the list. The 7 digit Product Number will be listed in both those places.
That series is over 3 years old now and those batteries usually come to their end of life about now. So it needs to be replaced, if you want a battery still. Its ok to remove it and only run on the power cord also.
Page 36 gives the details on the 2 different batteries used and how to access them.
That is a CTO model so there are no specs that can be looked up. It was configured to order by you (I assume) and Im guessing it has the larger graphics card installed. So it would take the larger battery.
The thing is that I have another laptop (exact same one) and its battery is still good
Means absolutely nothing. How much one laptop is used on battery over the other and the fact that there is no guarantee on how long any battery will last. Its already shown signs of failure in the battery test. I stand by what I said earlier.
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